Faith justifies a sinner in the sight of God, not because of those other graces which do always accompany it, or of good works that are the fruits of it, nor as if the grace of faith, or any act thereof, were imputed to him for his justification; but only as it is an instrument by which he receiveth and applieth Christ and his righteousness.
Adoption is an act of the free grace of God, in and for his only Son Jesus Christ, whereby all those that are justified are received into the number of his children, have his name put upon them, the Spirit of his Son given to them, are under his fatherly care and dispensations, admitted to all the liberties and privileges of the sons of God, made heirs of all the promises, and fellow-heirs with Christ in glory.
Sanctification is a work of God’s grace, whereby they whom God hath before the foundation of the world chosen to be holy, are in time through the powerful operation of his Spirit, applying the death and resurrection of Christ unto them, renewed in their whole man after the image of God; having the seeds of repentance unto life, and all other saving graces, put into their hearts, and those graces so stirred up, increased, and strengthened, as that they more and more die unto sin and rise unto newness of life.
Repentance unto life is a saving grace, wrought in the heart of a sinner by the Spirit and word of God, whereby, out of the sight and sense, not only of the danger, but also of the filthiness and odiousness of his sins, and upon the apprehension of God’s mercy in Christ to such as are penitent, he so grieves for and hates his sins, as that he turns from them all to God, purposing and endeavouring constantly to walk with him in all the ways of new obedience.
Although sanctification be inseparably joined with justification, yet they differ, in that God in justification imputeth the righteousness of Christ; in sanctification his Spirit infuseth grace, and enableth to the exercise thereof; in the former, sin is pardoned; in the other, it is subdued; the one doth equally free all believers from the revenging wrath of God, and that perfectly in this life, that they never fall into condemnation; the other is neither equal in all, nor in this life perfect in any, but growing up to perfection.
The imperfection of sanctification in believers ariseth from the remnants of sin abiding in every part of them, and the perpetual lustings of the flesh against the spirit; whereby they are often foiled with temptations, and fall into many sins, are hindered in all their spiritual services, and their best works are imperfect and defiled in the sight of God.
True believers, by reason of the unchangeable love of God, and his decree and covenant to give them perseverance, their inseparable union with Christ, his continual intercession for them, and the Spirit and seed of God abiding in them, can neither totally nor finally fall away from the state of grace, but are kept by the power of God through faith unto salvation.
Such as truly believe in Christ, and endeavor to walk in all good conscience before him, may, without extraordinary revelation, by faith grounded upon the truth of God’s promises, and by the Spirit enabling them to discern in themselves those graces to which the promises of life are made, and bearing witness with their spirits that they are the children of God, be infallibly assured that they are in the estate of grace and shall persevere therein unto salvation.
Assurance of grace and salvation not being of the essence of faith, true believers may wait long before they obtain it; and, after the enjoyment thereof, may have it weakened and intermitted, through manifold distempers, sins, temptations, and desertions; yet are they never left without such a presence and support of the Spirit of God, as keeps them from sinking into utter despair.